Matrix drill bits and method of manufacture

• US 20060231293A1
• Filed: 01/10/2006
• Published: 10/19/2006
• Est. Priority Date: 04/14/2005
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Brown, David A., Weaver, Gary, Ladi, Ram L.
• Granted Patent: US 7,398,840 B2
• Time in Patent Office: Days
• US Class Current: 175/374
• CPC Class Codes: B22D 19/06 for manufacturing or repairing tools
• CPC Class Codes: B22D 19/14 the objects being filamentary or particulate in form making alloys containing fibres or filaments by contacting the fibres or filaments with molten metal C22C47/08
• CPC Class Codes: B22D 23/06 Melting-down metal, e.g. metal particles, in the mould
• CPC Class Codes: B22F 2005/002 Tools other than cutting tools
• CPC Class Codes: B22F 7/062 involving the connection or repairing of preformed parts
• CPC Class Codes: C22C 29/06 based on carbides, but not containing other metal compounds
• CPC Class Codes: C22C 29/08 based on tungsten carbide
• CPC Class Codes: C22C 9/06 with nickel or cobalt as the next major constituent
• CPC Class Codes: E21B 10/00 Drill bits specially adapted for deflecting the direction of boring E21B7/064; with means for collecting substances E21B27/00
• CPC Class Codes: E21B 10/55 with preformed cutting elements

Abstract

A matrix drill bit and method of manufacturing a matrix bit body from a composite of matrix materials is disclosed. Two or more different types of matrix materials may be used to form a composite matrix bit body. A first matrix material may be selected to provide optimum fracture resistance (toughness) and optimum erosion, abrasion and wear resistance for portions of a matrix bit body such as cutter sockets, cutting structures, blades, junk slots and other portions of the bit body associated with engaging and removing formation materials. A second matrix material may be selected to provide desired infiltration of hot, liquid binder material with the first matrix material to form a solid, coherent, composite matrix bit body.

Claims

1. A drill bit having a matrix bit body comprising:

a plurality of cutting elements disposed at selected locations on exterior portions of the matrix bit body;

at least a first matrix material and a second matrix material with the first matrix material having increased resistance to impact as compared with the second matrix material;

the first matrix material forming exterior portions of the matrix bit body associated with engaging and removing formation materials from a wellbore;

the second matrix material forming interior portions of the matrix bit body which are generally not associated with engaging and removing formation materials from a wellbore; and

the second matrix material operable to improve infiltration of a hot, liquid binder material throughout the first matrix material to minimize incomplete infiltration of the first matrix material by the hot, liquid binder material.

2. The matrix drill bit of claim 1 wherein the matrix bit body further comprises:

the first matrix material selected from the group consisting of cemented carbides, composite carbides and spherical carbides; and

the second matrix material selected from the group consisting of macrocrystalline tungsten carbide powders, cast carbide powders and formulates thereof.

3. The matrix drill bit of claim 1 further comprising:

the binder material selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo) and alloys based of these metals; and

alloying elements selected from the group consisting of manganese (Mn), nickel (Ni), tin (Sn), zinc (Zn), silicon (Si), molybdenum (Mo), tungsten (W), boron (B) and phosphorous (P).

4. The matrix drill bit of claim 1 wherein the first matrix material further comprises pellets.

5. The matrix drill bit of claim 1 wherein the first matrix material further comprises composites of tungsten carbide.

6. The matrix drill bit of claim 1 wherein the matrix bit body further comprises at least a first zone of the first matrix material and at least a second zone of the second matrix material.

7. The matrix drill bit of claim 1 further comprising the second matrix material having a substantially reduced amount of alloys and other potential contaminants which may be leached by hot, liquid binder material as compared with alloys and other potential contaminants which may be leached by hot, liquid binder material from the first matrix material.

8. The matrix drill bit of claim 7 further comprising the second matrix material operable to accommodate alloys or other contaminates leached from the first matrix material by hot, liquid binder material without substantially reducing the quality of bonding formed by the hot, liquid binder material contacting and solidifying with the second matrix material.

9. The matrix drill bits of claim 1 wherein the matrix bit body further comprises a third matrix material covering the second matrix material.

10. The matrix drill bit of claim 9 wherein the third matrix material comprises at least in part a tungsten powder.

11. A drill bit having a composite matrix bit body comprising:

a plurality of cutting elements disposed at select locations on exterior portions of the bit body;

the composite matrix bit body having at least a first zone and a second zone disposed adjacent to each other;

the first zone formed at least in part by hard particles comprising cemented carbides and at least one binder material selected from the group consisting of cobalt, nickel, iron or alloys of these elements; and

the second zone formed at least in part from hard particles selected from the group consisting of macrocrystalline tungsten carbides and cast carbides; and

the second zone formed by the same binder material as the first zone.

12. The drill bit of claim 11 further comprising the second matrix material cooperating with the binder material to substantially reduce or eliminate unsoundness within interior portions of the composite matrix bit body.

13. The drill bit of claim 11 wherein the second matrix material comprises less than four percent alloy materials and other contaminates.

14. The drill bit of claim 11 wherein the first zone further comprises hard particles having an alloy concentration of less than approximately six percent.

15. The drill bit of claim 11 wherein the first zone further comprises the hard particles having an alloy concentration between approximately three percent and six percent.

16. The drill bit of claim 11 further comprising the first matrix material having a concentration of cobalt between about six percent and twenty percent.

17. The drill bit of claim 11 further comprising the second matrix material having increased wettability when exposed to hot, liquid binder material as compared with wettability of the first matrix material.

18. A method of making a matrix drill bit comprising:

placing at least a first layer of a first matrix material selected from the group consisting of cemented carbides and spherical carbides in a matrix bit body mold;

placing a hollow metal blank in the mold;

placing at least a second layer of a second matrix material selected from the group consisting of macrocrystalline tungsten carbide and cast carbide in the mold;

placing a binder material in the mold with the binder material proximate the second layer of matrix material and the hollow metal blank;

heating the mold and the materials disposed therein in a furnace to a selected temperature to allow the binder material to melt and to infiltrate the second matrix material and the first matrix material with hot, liquid binder material;

starting solidification of the hot, liquid binder material with the first matrix material before the hot, liquid binder material solidifies with the second matrix material; and

cooling the mold and materials disposed therein to form a coherent composite matrix bit body securely engaged with the hollow metal blank.

19. The method of claim 18 further comprising:

placing a sand core having a generally cylindrical configuration defined in part by an outside diameter in the mold;

placing the hollow metal blank over the sand core to form an annulus defined in part by an inside diameter of the hollow metal blank and the outside diameter of the sand core; and

filling the annulus between the sand core and the hollow metal blank with the second matrix material.

20. The method of claim 18 further comprising:

installing a sand core in the mold with one end of the sand core spaced from the first layer of the first matrix material; and

placing portions of the second matrix material between the one end of the sand core and adjacent portions of the first layer of the first matrix material.

21. The method of claim 18 further comprising forming interior portions of the composite matrix bit body with the second matrix material.

22. The method of claim 18 further comprising forming exterior portions of the composite matrix bit body associated with engaging and removing downhole formation materials with the first matrix material.

23. The method of claim 18 further comprising transporting alloys and other potential contaminates leached from the first matrix material to the second matrix material by hot, liquid binder material prior to solidification of the second matrix material.

24. The method of claim 18 further comprising placing a third layer of matrix material on the second layer of matrix material prior to placing the binder material in the mold.